09.06.2026

SAP ECC Maintenance End 2027 and SAP S/4HANA Migration: Why Your SAP Master Data Is Crucial Now

Master data quality as the basis for a successful SAP S/4HANA migration

The maintenance end date for SAP ECC is approaching. The S/4HANA migration is slowly but surely coming under pressure. Many SAP user companies are still facing the decision: What happens after SAP ECC 2027, when do we migrate to SAP S/4HANA, and what preparations are necessary now?

Strict maintenance deadlines from SAP, unavoidable process modernizations, and the rapid growth of artificial intelligence are making SAP S/4HANA transformation projects increasingly complex. Besides careful planning, an often underestimated factor determines the smooth execution of the migration: the quality of the SAP master data.

What is often a long-standing problem comes to light during an SAP S/4HANA migration: outdated, faulty, or incomplete SAP data. This is frequently compounded by unclear processes that have evolved over years, customizations documented only in the minds of long-term employees, or a heterogeneous system landscape. Those who address this issue proactively and improve data quality early on gain a long-term advantage and benefit not only during the migration to SAP S/4HANA.

What is an SAP S/4HANA migration?

An SAP S/4HANA migration involves a company switching from existing SAP ECC systems to the new ERP generation, SAP S/4HANA. This new generation is optimized for the in-memory database SAP HANA. Migrating to the current system variant offers several advantages, including:

• Standardization and automation of business processes
• Harmonization of global data structures and consistent data management
• Real-time analytics and potential for AI applications
• Modernization and improvement of the user experience (UX) through SAP Fiori

What approaches are available for SAP S/4HANA migration?

• Brownfield approach: This involves a purely technical conversion of existing systems. Historical data is transferred during the data migration. This approach is particularly suitable for companies with a stable foundation. However, those who view migration as simply replacing software architectures miss out on significant optimization potential.
• Greenfield approach: SAP S/4HANA is implemented from scratch. Processes and structures are optimized and redefined. This presents a genuine opportunity to enter the new environment with high data quality, significant clean core potential, and an optimal foundation for new technologies such as AI.
• Selective Data Transition: Selected processes and data are selectively migrated, while others are optimized during the migration process. A new SAP S/4HANA system is being implemented. This is a clever combination of the two previously described approaches in a hybrid model.

What is Business Partner Conversion?

In SAP S/4HANA, the customer and vendor model is replaced. Customers and vendors are merged into the Business Partner. Migrating to the SAP Business Partner often involves significant effort, as it requires, among other things, eliminating duplicates, harmonizing roles and attributes, and removing outdated data. Customer Vendor Integration (CVI) also presents a challenge for many companies. Besides planning the Business Partner Conversion early, a well-maintained database offers an advantage for this part of the SAP S/4HANA migration as well.

Why are SAP data and data quality crucial for SAP S/4HANA migration?

Business processes are based on SAP master data, such as customer master data, vendor master data, material master data, financial master data, and business partner data. Typical consequences of poorly maintained SAP master data include duplicates, inconsistent material numbers, and faulty reports. These lead to delays in the migration project, significant manual effort during post-processing, and interface problems. Therefore, master data quality (regardless of the migration approach) is a key success factor for SAP S/4HANA migration.

Transferring historical data from the legacy system without data cleansing will prevent you from optimally utilizing the new system. Failing to implement a clear data governance strategy will inevitably lead to inconsistencies due to unclear responsibilities. Since data expertise often resides directly within the business units, it is crucial to involve them from the outset.

Improving data quality before migrating to SAP S/4HANA is worthwhile to avoid delays caused by inconsistent master data. Have you already completed the migration and want to optimize data creation and maintenance, thereby fundamentally improving data quality? With proven solutions like APICON Data Master, you can quickly and easily improve data quality directly within SAP. Your master data processes will be accelerated, and manual effort will be reduced.

Read this blog post to discover SAP's maintenance deadlines, things you need to consider now, and the APICON Data Master roadmap.